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• Computer networking
• Foundation of computer network


  • Switches
  • Routers
  • Access points
• Connect and help to internally secure devices to network

  • SWITCHES
• Access points

  • Are switches that connect devices to networks without the use of cables
• ROUTERS

  Connect networks to other networks and act as "dispatchers"

  • Analyze data to be sent across a network, choose the best routes for it, and send it on its way
  • Connect your home and business to the world and help protect information from outside security threats
  • A Layer 3 router uniquely identifies a device's network connection with a network-assigned IP address
• MAC address

  A number assigned to a network interface card (NIC) by a device's manufacturer
• IP address

  A number assigned to a network connection
• LAN (Local Area Network)

  • Computer network that connects computers within the limited area such as schools, colleges or universities
  • Are privately-owned networks
  • Provide a useful way of sharing resources between end users
  • Resources are easily sharable among other connected computers in a network
  • Operate at relatively high speed as compared to the typical WAN
  • Work in a relatively small geographical area
• Advantages of LAN

  • Resource Sharing
  • Software Applications Sharing
  • Easy and Cheap Communication
  • Centralized Data
  • Data Security
  • Internet Sharing
• MAN (Metropolitan Area Network)

  • A large computer network that usually spans a city or a large campus
  • Optimized for a larger geographical area than a LAN, ranging from several blocks of buildings to entire cities
  • Formed by connecting multiple LAN
  • The purpose of MAN is to provide the link to the internet in the long run
  • MAN Network provides Internet connectivity for LANs in a metropolitan region, and connect them to wider area networks like the Internet
  • Network size (5-50km)
  • It may be as small as a group of buildings on campus to as large as covering the whole city
  • MAN is either owned by a user group or by a network provider who sells service to users
  • Data rates are moderate to high
  • It facilitates the sharing of regional resources
  • They provide uplinks for connecting LANs to WANs and the Internet
• Disadvantages of MAN

  • Difficult to Manage
  • Internet Speed Difference
  • Hackers Attack
  • Technical Staff Requires to Set up
  • Need More wires
• WAN (Wide Area Network)

  • Computer network that connects computers within a large geographical area comprising a region, a country, a continent or even the whole world
  • Mostly public, leased or privately-owned networks
  • Provide a useful way of sharing resources between the end users such as the long-distance transmission of data over large geographical areas
  • The best example of a Wide Area Network is the Internet which connects many smaller LANs and MANs through Internet service providers
  • WANs are owned by third-party service providers
  • WAN must be able to grow as needed to cover multiple cities, even countries, and continents
• Distinguishing feature of WAN

  • Covers Large Geographical Area
  • Centralized Data
  • Get Updated Files and Data
  • Sharing of Software and Resources
  • High Bandwidth
• Disadvantages of WAN

  • Security Problems
  • Needs Firewall and Antivirus Software
  • The Setup Cost is High
  • Troubleshooting Problems
  • Maintenance Issues
• ISP

  Is the company that provides you with your Internet connection
• LAN

  A small network that's confined to a local area. (home network or an office network)
• WAN

  A larger network that covers a wider area. Your ISP provides you with a connection to their own WAN, which connects to the Internet
• IP Address

  An Internet Protocol address, or IP address, is a numerical address that corresponds to your computer on a network. When a computer wants to connect to another computer, it connects to that computer's IP address
• IPv4

  Older, Most common
• IPv6

  Newer, Necessary because we just don't have enough IPv4 addresses for all the people and devices in the world
• Router

  • A device that passes traffic back and forth. A router's job to pass outgoing traffic from your local devices to the Internet, and to pass incoming traffic from the Internet to your devices
• Gateway

  A device that routes traffic between networks
• Network Address Translation (NAT)

  Used by routers to share a single IP address among many devices. Your ISP provides you with a single IP address that's reachable from anywhere on the Internet, sometimes called a public IP address. Your router creates a LAN and assigns local IP addresses to your devices. The router then functions as a gateway. To devices outside your LAN, it appears as if you have one device (the router) using a single IP address
• Dynamic Host Configuration Protocol (DHCP)

  Allows computers to automatically request and be assigned IP addresses and other network settings. When you connect your laptop or smartphone to your Wi-Fi network, your device asks the router for an IP address using DHCP and the router assigns an IP address
• Hostnames

  A human-readable label that points to a device connected to a network
• Domain Name

  Are the base part of website names. Domain names are just another type of hostname
• Domain Name System (DNS)

  How computers convert human-readable domain names and hostnames to numerical IP addresses
• Ethernet

  The standard wired network technology in use almost everywhere today
• Network Interface / Network Adapter

  Your computer's wired Ethernet connection and Wi-Fi connection are basically both network interfaces. If your laptop was connected to both a wired connection and a Wi-Fi network, each network interface would have its own IP address. Network interfaces can also be implemented entirely in software, so they don't always directly correspond to hardware devices
• Localhost

  The hostname "localhost" always corresponds to the device you're using. This uses the loopback network interface, a network interface implemented in software to connect directly to your own PC
• MAC Address (Physical Address)

  This is a unique identifier designed to identify different computers on a network. MAC addresses are usually assigned when a manufacturer creates a network device
• Port

  When an application wants to send or receive traffic, it has to use a numbered port between 1 to 65535. This is how you can have multiple applications on a computer using the network and each application knows which traffic is for it
• Protocol (TCP, UDP, ICMP, etc)

  Are different ways of communicating over the Internet. TCP and UDP are the most common protocols. The ICMP protocol is also used, but primarily so network devices can check each other's status
• Packet


  A unit of data sent between devices. The packet is the basic unit of data that computers on a network exchange
• Firewall

  A piece of software or hardware that blocks certain types of traffic. A firewall could block incoming traffic on a certain port or block all incoming traffic except traffic coming from a specific IP address
• Hyper Text Transfer Protocol (HTTP)

  The standard protocol modern web browsers and the web itself uses. FTP and BitTorrent are examples of alternative protocols
• Uniform Resource Locator/Web Address

  The current URL is displayed in your web browser's address bar
• Data Network

  A system that transfers data between network access points (nodes) through data switching, system control and interconnection transmission lines. Data networks are primarily designed to transfer data from one point to one or more points (multipoint)
• Connect networks to other networks and act as "dispatchers"

  • Analyze data to be sent across a network, choose the best routes for it, and send it on its way
  • Connect your home and business to the world and help protect information from outside security threats
  • A Layer 3 router uniquely identifies a device's network connection with a network-assigned IP address

• PEER-TO-PEER NETWORKS

  Connect computers so that each computer shares all or part of its resources.  Involve two or more computers pooling individual resources such as disk drives, DVD players and printers.